Sylvania



reason of not being properly supplied with MOSES C. HAWKINS, JACOB 7.GOODWIN,

AND JAMES CUMMINGS, OF ERIE, PENN- SYLVANIA.

SPRING-VALVE COCK.

Specification of Letters Patent No.

To all whom 'it may concern:

Be it known that we, MOSES C. HAWKINS, JACOB T. GOODWIN, and JAMESCUMMINGS, of the city and county of Erie and State of Pennsylvania, haveinvented an Improvement in Air-Cocks for Force-Pumps, the nature ofwhich invention we do hereby declare to be fully described and setforthin the following description and specification.

In connection with the ordinary air-cock, we employ, first, theair-valve Z, as shown in the accompanying drawing B, or its mechanicalLequivalent; second, the valve-gage Y, and spiral spring V, as describedin the same drawing. These several parts form in combination with eachother and with the ordinary air-cock, the peculiar mechanicalcontrivance which we call a valve aircock;7 and which we claim to benew, as well as highly useful and important.

Te will explain the utility of the improvement which we claim to haveinvented, with the manner of its operat-ion, as applied to theforce-pump of a steam engine. It is a well established fact, that air,or vapor, or both together, often accumulates in the barrel of the pump,between the stuffing box and feed-valve, and by its presence there,prevents a full and uniform action of the pump. The air, as it becomescondensed by continued accumulation, expands and fills the vacuum whichis intended to be produced by the withdrawal of the plunger or pistonrod, so that the natural pressure of the atmosphere upon the water inthe well or reservoir, is insufficient to force the water through thefeed-valve into the pumpbarrel, there being really no vacuum produced bythe withdrawal of the plunger, in consequence of the expansion of thecondensed air and vapor in the pump-barrel, as described. Under suchcircumstances, the force pump must of course, at once become useless,and much danger thereupon arise to engine and boiler, as it is wellknown that steam boilers often explode for the water by the force pump.By applying the valve air cock to the barrel 0f the pump,

18,8417, dated December 15, 1857.

near the stuffing box, as described in drawing D, accompanying, thisdiiiculty is completely overcome, securing to the force pump a full andregular action. The operation of the valve air-cock, may be thusdescribed:

Then the air or vapor accumulates in the pump-barrel, so as to impairthe due working of the pump, it will, on turning the cock as describedin drawing B, escape, as the plunger passes in, by forcing back thevalve Z, which is instantly closed by the external pressure of theatmosphere, the moment the plunger begins to be drawn back, exceptingwhen the external pressure upon the valve, is less than the internalpressure of the expanding air. Then the air and vapor has escaped, thecock should be turned back, as in drawing D. Then the accumulated air isagain found to cause trouble, again turn the cock, as described, and letit escape. It will be seen that by `employing such an air cock as wehave described, the force pump may be relieved of the air detrimental toits action, without in mean time at all impairing or suspending the dueworking of the pump, no matter how rapid the motion of the plunger maybe, an important object which can be accomplished by no air cockheretofore known or used. It remains to be explained, that thevalve-gage Y, and the spiral spring V, are employed for the purpose ofassisting to keep the valve Z in its place and gaging its motion.

Te do not claim any part of the air cock, constructed as described, whentaken separately. Bute- Te do claim- The valve Z, valve-gage Y, withspiral spring V, in combination wit-h the ordinary air cock, in themanner described, and for the purpose set forth.

MOSES C. HAWKINS. JACOB T. GOODVIN. JAMES CUMMINGS. Titnessest J. F.DOWNING, WM. A. GRIswoLD.

